Today blood collection organizations routinely separate whole blood by centrifugation into its various therapeutic components, such as red blood cells, platelets, and plasma.
Conventional blood processing systems and methods use durable centrifuge equipment in association with single use, sterile processing chambers, typically made of plastic. The centrifuge equipment introduces whole blood into these chambers while rotating them to create a centrifugal field.
Whole blood separates within the rotating chamber under the influence of the centrifugal field into higher density red blood cells and platelet-rich plasma. An intermediate layer of white blood cells and lymphocytes forms an interface between the red blood cells and platelet-rich plasma.
In conventional blood separation systems and methods, it is important to monitor the position of the interface during processing, to keep the formed elements in the interface and red blood cells adjacent to the interface from entering the platelet-rich plasma stream.